CNC Machinist Job Description

A CNC machinist turns a drawing and a piece of bar stock, plate or casting into a finished metal part on a computer-controlled mill, lathe or machining center. O*NET files the work under Machinists (51-4041.00) and lists CNC machinist among the reported job titles for that occupation. Much of the job happens before the spindle turns.

Planning the job. The machinist starts with the print. That means reading the title block, the material callout, the surface finish notes and the GD&T frame on each feature: true position on a bolt pattern, flatness on a sealing face, runout on a bearing journal. From there the machinist decides how the part will be held, which side gets cut first, and which tools will cut each feature. On a mill that might be a pair of vises, a set of soft jaws or a fixture plate, indicated square to the X axis. On a lathe it means choosing a chuck or collet, boring soft jaws to size, and loading the turret.

Programming and prove-out. Some parts are simple enough to program or adjust at the control. Others come out of a CAM package such as Mastercam or Autodesk Fusion, where toolpaths are built on a 3D model and posted as G-code for one specific machine. Either way, the machinist owns the prove-out. That means running the first part in single block, watching distance-to-go on the screen, and keeping a hand near feed hold as each tool approaches the stock for the first time.

First article and process control. Once the first part is off, every critical dimension gets measured with micrometers, bore gauges, height gauges, thread gauges or a coordinate measuring machine, and offsets are adjusted until the part matches the print. BLS notes that the work sometimes demands accuracy to within .0001 of an inch. During a production run the job shifts to watching the process: checking parts at a set frequency, tracking tool wear, listening for chatter, clearing chips, and bumping wear offsets before a dimension walks out of tolerance.

Material and tooling judgment. Titanium, Inconel 718 and 17-4 stainless each punish the wrong speed, feed or coolant choice in their own way. Aluminum brings a different problem: built-up edge and chip evacuation at high spindle speeds. Picking the insert grade, the step-over and the depth of cut for the material is where an experienced machinist earns the job title.

Paperwork that keeps parts moving. A good setup sheet lists the tools, stick-out lengths, work offsets, fixture locations and notes on what went wrong, so the job can be rerun next quarter without starting from scratch. In shops that make aerospace or defense parts, a traveler follows each part through every operation, and first-article inspection reports may go to the customer.

Where the work happens. Job shops, contract machine shops and the in-house machining departments of companies that build engines, pumps, valves, medical devices and aircraft structures all hire for this title. BLS notes that some machinists work nights and weekends in facilities that operate around the clock, and that some work more than 40 hours a week.

Education. BLS says machinists typically need a high school diploma or equivalent, and it names math, blueprint reading, metalworking and CAD/CAM as useful high school courses. Some community colleges and technical schools offer 2-year degrees and shorter certificate programs that teach reading engineering drawings and the programming and function of CNC machines. Look for a program that puts students on real mills and lathes, not only simulators.

Training on the floor. The usual path is on-the-job training. BLS notes that trainees often begin as machine operators and gradually take on more difficult assignments. As a rough guide, expect two to four years of setup work before a shop trusts you alone with unproven programs on its most expensive machine.

Apprenticeship. BLS describes apprenticeship programs as typically sponsored by an employer and consisting of paid on-the-job training plus related technical instruction lasting several years. One registered example shows what that looks like in practice: a CNC machinist apprenticeship standard approved by the Washington State Apprenticeship and Training Council on July 15, 2021 sets an 8,000-hour term. Its work process schedule assigns approximately 3,100 hours to turning, 1,000 hours to milling and 500 hours to precision measurement and inspection, including GD&T, with a minimum of 176 hours of related supplemental instruction per year.

Credentials. BLS calls certification optional but says it lets machinists demonstrate competency and may help with advancement. The credentials a CNC machinist would actually pursue:

• NIMS CNC Mill Programming Setup & Operations and CNC Lathe Programming Setup & Operations (National Institute for Metalworking Skills)
• NIMS CNC 5-Axis Milling Operator and CNC 5-Axis Milling Specialist (National Institute for Metalworking Skills)
• NIMS CAM Milling Programmer and CAM Turning Programmer (National Institute for Metalworking Skills), for machinists moving toward programming
• OSHA 10-Hour General Industry card (OSHA Outreach Training Program)

Skills to bring to the interview.

• Controls: Fanuc, Haas, Mazak Mazatrol, Okuma OSP and Siemens Sinumerik each handle offsets and editing differently, so name the ones you have run.
• CAM: Mastercam, Fusion, GibbsCAM or NX, at least well enough to read a toolpath and spot a gouge.
• Metrology: micrometers, bore gauges, height gauges, indicators, thread gauges and basic CMM reports.
• Shop math: trigonometry for bolt circles and chamfers, and the speed and feed formulas.
• Workholding: indicating vises, tramming heads, boring soft jaws and building simple fixtures.

Physical side. BLS notes that machinists stand for extended periods and perform repetitious movements, and that workers must wear protective equipment such as safety glasses against flying metal and earplugs against machine noise. Setups involve lifting fixtures, vises and bar stock, so plan on steel-toe boots.

The projection. BLS projects overall employment of machinists and tool and die makers to decline 1 percent from 2025 to 2035. The two halves move differently: the BLS projections table shows machinists alone growing 1 percent over the decade, against 3 percent for all occupations, while tool and die makers fall 9 percent. For a job seeker, the openings figure is the one to watch. BLS expects about 30,400 openings a year on average for machinists and tool and die makers combined, and it says all of those openings come from the need to replace workers who move to other occupations or leave the labor force, such as to retire.

Why growth is flat. BLS ties the machinist forecast to the equipment itself. Machinists will still be needed to set up, monitor and maintain CNC machine tools, autoloaders and high-speed machining, the agency says, but employment growth is expected to be limited as improvements in those technologies increase each worker's efficiency. For an individual machinist, that reads as a case for being the person who can set up, program and troubleshoot the automated cell rather than the person who loads it.

Where the jobs are. Machinists held about 288,300 jobs in 2025, according to BLS. Fabricated metal product manufacturing accounted for 35 percent of them, machinery manufacturing for 21 percent, and transportation equipment manufacturing for 13 percent. That spread matters when you job hunt: a contract job shop, an engine plant and an aircraft parts supplier hire for the same title but run very different work, from short-run prototypes to long production runs on dedicated machines.

Pay. The national median annual wage for machinists was $58,750 in May 2025. Some machinists become tool and die makers, according to BLS, and that occupation had a median annual wage of $64,050 in May 2025. Other paths out of the machine include CNC programming, manufacturing engineering, quality inspection and shop supervision, each of which builds on the same print-reading, setup and metrology base.

Material costs and the shop floor. Machinists who quote jobs or work in small shops will notice metal prices. According to a Congressional Research Service insight updated September 17, 2026, the United States raised Section 232 tariffs on steel and aluminum to 50 percent for most trading partners in June 2025, and an April 2026 change applied those tariffs to the full value of goods rather than only their metal content. The same CRS insight said that, as of that update, the tariffs covered steel, aluminum and derivative products from nearly all trading partners. How that plays out in a given shop depends on where its bar, plate and forgings come from.

Skills that hold value. Multi-axis setup, CAM programming, GD&T and inspection are the skills that let a machinist own a job from print to finished part. Those tasks still need a person when a shop adds a pallet changer or a robot loader: someone still has to prove the program, set the offsets and decide whether the first part is good. Those same skills are the base for a lead role, a programming desk, or a shop of one's own.

Dear Hiring Manager,

I am applying for the CNC Machinist opening at your shop. For the past five years I have worked at a contract machine shop that makes valve bodies, pump housings and small aerospace brackets in lots of five to five hundred pieces.

Most of my time is on two Haas vertical machining centers and a Doosan lathe with live tooling. I set up my own jobs from the print: I choose the workholding, load and measure the tools, set work offsets, and prove out the program in single block before I let the machine run. I program simple parts at the control and use Mastercam for anything with 3D contours, then edit the posted code at the machine when something needs to change.

The job I am proudest of was a stainless manifold with a tight true position callout on a cross-drilled pattern. The first setup kept missing on the second side. I built a dedicated fixture with a locating pin and a hard stop, rewrote the setup sheet, and we have run that part on three reorders since without a scrapped piece.

I hold NIMS credentials in CNC milling and turning setup and operations, and I am working toward the 5-axis milling credential because I want to move onto five-axis work. Your shop's mix of five-axis milling and mill-turn work is the reason I am applying here rather than to another three-axis shop.

I keep a binder of setup sheets, first-article reports and photos of fixtures I have built, and I would be glad to walk you through it. I am available for an interview and a shop-floor test at your convenience.

Sincerely, [Your Name]